(1) Field of the Invention
The present invention relates to an improved structure for a coaxial cable connector, and more particularly, to improved hermetic structure for a coaxial cable connector which is able to perfectly shut out moisture therefrom.
(2) Description of the Prior Art
A coaxial cable connector is very well known to people who engage in the work of electronic and communication cable engineering. An F type coaxial cable connector is typically screw combined to an auxiliary interface connector for electrically joining integrally a coaxial cable to various electronic devices such as TV, CB, FM radio receiver or amateur radio systems.
A conventional coaxial cable connector transmits electrical signals by reliably engaging its connector with the coaxial cable shielding layer. However, one of the shortcomings of a conventional coaxial cable connector is its susceptibility to moisture infringement, that is, the moisture infringes into the connector through the clearance between the connector body and the interface connector.
FIG. 1 is a cross sectional view of a conventional coaxial cable connector in engagement with an interface connector. As shown in FIG. 1, an F type connector is used as a representative example for all conventional coaxial cable connectors. The F type coaxial cable connector 10 consists of a connector body 11, an axle collar 12, a stem 13 co-axially disposed within the axle collar 12, and a nut 14 surrounding the stem 13. The connector 10 further includes a sealing element 15 sandwiched between the inner surface of the nut 14 and the outer surface of the stem 13.
Both the insulating layer and the center conductor of the coaxial cable are inserted within the stem 13 by aligning a terminal 16 of the connector body 11 coincident with the end of the connector 10 so that the connector is engaged with the coaxial cable. Both braided shielding layer and cable jacket are interposed between the outer surface of the stem 13 and the axle collar 12 and are connected by exerting a compressive force with a hexagonal compression tool to the axle collar 12 so as to hermetically engage the connector 10 with the cable jacket.
Incidentally, there is a problem inherent to the combination of the F type coaxial cable connector 10 and an interface connector 17. That is, the infringement of moisture may occur at the incomplete screw contact surfaces between the nut 14 and the interface connector 17, as shown by arrow 18. The infringement of moisture through the clearance shown by arrow 18 between the nut 14 and the interface connector 17 can be prevented by filling a sealing element 15 therebetween. However, the infringement of moisture 19 can further occur at the contact surface between the interface connector 17 and the stem 13 with the result of leaking of wire TV wave and degrading the signal transmission property of the connector 10. Consequently, the infringement of moisture 19 between the interface connector 17 and the stem 13 still has to be eliminated.
FIG. 2 is a cross sectional view showing the state of an output/input terminal coupling relation between a conventional interface connector and an electronic device. FIG. 2 shows that the infringement of moisture may occur at the incomplete contact surfaces between the nut 14 and an electronic device 101. The infringement of moisture 102 can be excluded by means of filling a rubber element 103 thereinto. But such a treatment requires consumption of additional material and increases the manufacturing cost and time.